Dataset Information

MNX1-AS1, a c-Myc induced lncRNA, promotes the Warburg effect by regulating PKM2 nuclear translocation

ABSTRACT: Altered glycolysis is the most fundamental metabolic change associated with the Warburg effect. However, the precise mechanisms are not completely understood. Here we dissect how MNX1-AS1 reinforces the Warburg effect through facilitating the non-glycolytic actions of PKM2 in the nucleus. We found that MNX1-AS1 expression was frequently overexpressed in hepatocellular carcinoma (HCC). In the context of HCC, we show MNX1-AS1 acts as a scaffold to promote interactions between PKM2 and importin α5. Upon EGFR activation, the resulting ternary complex drives the translocation of PKM2 into the nucleus. In consequence, glycolytic pathway components including key mediators of the Warburg effect (LDHA, Glut1 and PDK1) are upregulated. Manipulating MNX1-AS1 elicited robust effects on glycolysis associated with marked changes in HCC growth in vitro and in vivo, indicative of the significant contribution of MNX1-AS1 to tumorigenesis. Moreover, while MNX1-AS1 expression is driven by c-Myc, its actions associated with PKM2 were shown to be downstream and independent of c-Myc. Given the status of MNX1-AS1 as a pan-cancer upregulated lncRNA, this implicitly highlights the potential of targeting MNX1-AS1 to selectively counter the Warburg effect in a range of tumor types.

ORGANISM(S): Homo sapiens

PROVIDER: GSE213064 | GEO | 2022/11/23

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:Many cancers rely on glycolytic metabolism to fuel rapid proliferation. This has spurred interest in designing drugs that target tumor glycolysis such as AZD3965, a small molecule inhibitor of Monocarboxylate Transporter 1 (MCT1) currently undergoing Phase I evaluation for cancer treatment. Since MCT1 mediates proton-linked transport of monocarboxylates such as lactate and pyruvate across the plasma membrane (Halestrap and Meredith, 2004), AZD3965 is thought to block tumor growth through disruption of lactate transport and glycolysis. Here we show that MCT1 inhibition impairs proliferation of glycolytic breast cancer cells that express MCT4 via disruption of pyruvate rather than lactate export. We found that MCT1 expression is elevated in glycolytic breast tumors and cell lines as well as in malignant breast and lung tissues. High MCT1 expression predicts poor prognosis in breast and lung cancer patients. Stable knockdown and AZD3965-mediated inhibition of MCT1 promote oxidative metabolism. Acute inhibition of MCT1 reduces pyruvate export rate but does not consistently alter lactate transport or glycolytic flux in breast cancer cells that also express MCT4. Despite the lack of glycolysis impairment, MCT1 loss-of-function decreases breast cancer cell proliferation and blocks growth of mammary fat pad xenograft tumors. Our data suggest that MCT1 expression is elevated in glycolytic cancers to promote pyruvate export, which when inhibited enhances oxidative metabolism and reduces proliferation. This study presents an alternative molecular consequence of MCT1 inhibitors that further supports their use as anti-cancer therapeutics. Since MCT1 levels are elevated in glycolytic and malignant breast tumors, we hypothesized that MCT1 may contribute to the Warburg effect metabolic phenotype. To test this hypothesis, we generated whole genome microarray data from breast cancer cell lines either a) expressing a short hairpin (sh)RNA-mediated stable knockdown of MCT1; or b) treated for 24 hours with an MCT1 inhibitor (AZD3965). Scramble shRNA or DMSO were used as controls, and all conditions were analzed in triplicate. The cell lines used â HS578T, SUM149PT, and SUM159PT â are among the most glycolytic in a panel of 31 breast cancer cell lines.

Dataset Information

MNX1-AS1, a c-Myc induced lncRNA, promotes the Warburg effect by regulating PKM2 nuclear translocation

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure